Seikan Tunnel

The idea of tunneling beneath the English Channel began circulating in the early 19th century. In 1986, Britain and France signed a treaty authorizing the construction of a tunnel running between Folkestone, England, and Calais, France. Construction on the Chunnel (channel-tunnel) began in 1988. On December 1, 1990, 132 feet below the English Channel, workers drill an opening the size of a car through a wall of rock. This was no ordinary hole–it connected the two ends of an underwater tunnel linking Great Britain with the European mainland for the first time in more than 8,000 years. After workers drilled that final hole, they exchanged French and British flags and toasted each other with champagne.

Over the next four years, nearly 13,000 workers dug 95 miles of tunnels at an average depth of 150 feet below sea level. Eight million cubic meters of soil were removed, at a rate of some 2,400 tons per hour. The completed Chunnel would have three interconnected tubes, including one rail track in each direction and one service tunnel. At a cost of over $21 billion, the 31.4 mile-long Channel Tunnel was completed in 1994, and officially opened by Queen Elizabeth II and President Mitterrand. With regular maintenance and upkeep, the Chunnel allows for millions of passengers travel between London and Paris each year – both for business and pleasure!

A company called Eurotunnel won the 55-year concession to operate the Chunnel, which is the crucial stretch of the Eurostar high-speed rail link between London and Paris. The regular shuttle train through the tunnel runs 31 miles in total–23 of those underwater–and takes 20 minutes, with an additional 15-minute loop to turn the train around. The Chunnel is the second-longest rail tunnel in the world, after the Seikan Tunnel in Japan.

The Channel tunnel was one of the largest construction projects of the 20th century and remains a marvel of engineering even today. It was selected by American Society of Civil Engineers as one of the Seven Wonders of the Modern World in 1996.